The invention relates to a picture transmission system of a guided missile which is connected with a ground facility by means of an optical wave guide.
In the case of guided missiles of this type, it is known to carry out a real-time picture transmission from a camera installed in the tip of the guided missile. As a result of the high band width by way of the optical wave guide, measured values of the instrumentation can at the same time be transmitted to the ground facility together with the picture data and, in the opposite direction, the necessary control and switching commands for the guiding of the guided missile can be transmitted from the ground. By means of the pictures of a TV-camera or an IR-camera, the missile-firing person can navigate the guided missile into a specific target area and he can also use the camera to detect existing targets, identify them and therefore attack them. Since it may be assumed that the flight into the target area takes place in the first instance according to map information and support by means of guided-missile gyroscopes, a lens coverage is required for orientation during navigation that is as large as possible, for it increases the chances of detecting clearly defined points in the terrain. Predominantly focal lengths of the lens of approximately 28 mm are to be suggested for this navigational task in the case of commercially available 2/3-inch CCD-arrays of the TV camera.
In contrast, for early target recognition and identification, the person firing the missile needs large focal length lenses--thus telephoto lenses--which, however, have a correspondingly smaller angular lens coverage. When the above-mentioned CCD-arrays are used, focal lengths of between 80 mm and 100 mm are recommended, because at larger focal lengths--for example, 200 mm and more--limits exist with respect to the stabilizing quality of the platform on which the camera is disposed.
On the basis of the German Published Examined Patent Application (DE-AS) 24 11 791, a picture transmission system of a guided missile is known which is connected by way of an optical wave guide with a ground facility and comprises a camera arranged in the tip of the guided missile which carries out a real-time picture transmission by way of the optical wave guide.
From the German Patent Document (DE) 31 46 552 C2, it is also known to transmit continuously to the ground facility two lens coverages as continuous pictures by means of two cameras of different focal lengths to which one picture array respectively is assigned. In this case a track window is faded into the center of the one lens coverage and, for purposes of identification, the track window is aimed at the point to be enlarged and the picture of this point is displayed on an identification monitor.
In the commonly owned pending German Patent Application (DE-OS) 39 27 334 (not prior art) the applicant suggested a real-time picture transmission device for a camera with two focal lengths in which the lens for the large focal length and the lens for the short focal length form a single structural element, and the change-over from one focal length to the other focal length takes place by means of the electronic system of the camera.
Thus, by means of the correspondingly designed camera with two focal lengths, the pictures are available simultaneously for the purpose of navigation as well as for the purpose of identification. It was found, however, that, for a simultaneous transmission of both pictures, the expenditures in the guided missile--which may be called a disposable or "lost missile"--are very high. Thus, at least two electronic systems for the camera are required, as well as a supplementary electronic system which "nests" the line information of both arrays in one another with a double frequency, and the double frequency is also needed for the transmission by way of the optical wave guide to the ground.
It is an object of the present invention to provide, based on the picture transmission system of the above-noted '334 application, a system which no longer requires these expenditures and nevertheless meets all tactical requirements, such as fast change-over times, high pivoting speed of the camera and large pivoting angles and, at the same time, saves space and weight and increases the overall efficiency of the system.
This object is achieved by providing a visual image transmission system for a guided missile which is connected with a ground facility comprising:
a camera disposable in a guided missile and having a first lens of short focal length for sensing navigation aiding images and a second lens of long focal length for sensing target identification aiding images, PA1 a navigational visual display device at a ground facility, PA1 a target identification visual display device at the ground facility, PA1 and optical wave guide and electro-optical transmitting means for transmitting the visual image from the first lens to the navigational visual display device and for transmitting the visual image from the second lens to the target identification visual display device, PA1 wherein means are provided for selectively displaying the target identification image as a still picture on the target identification visual display device without impairing continuous viewing of the navigational aiding images on the navigational visual display device.
In especially preferred embodiments of the invention, the two lenses are constructed as composite fixed focal length lens where the short focal length lens is disposed in the center of the long focal length lens.
According to especially preferred embodiments, a camera optical wave guide is used to transmit the images from both lenses as well as control signals for controlling the missile. In preferred operational modes, the identification picture is transmitted for short periods while interrupting the navigational picture, without disrupting the missile operators continuous perception of the movng navigational images. Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.